[DeTomaso] Mike Drew's Dyno Test Results

Jørn C. Olsen joernco at online.no
Wed May 19 15:43:18 EDT 2010


Nice figures Dan and Mike!

J.C.

-----Opprinnelig melding-----
Fra: detomaso-bounces at realbig.com [mailto:detomaso-bounces at realbig.com] På
vegne av Daniel C Jones
Sendt: 19. mai 2010 05:10
Til: Pantera REALBIG forum
Emne: [DeTomaso] Mike Drew's Dyno Test Results

Mike Drew, Dave McLain and I spent a day on the dyno recently, testing
Mike's
new 408C engine.  Specs of Mike's engine are:

 Bobby Oliver (Competition Carburetion in Nevada) modified 750 CFM
Holley double
 pumper with electric choke
 Blue Thunder dual plane aluminum intake manifold
 CHI-4V aluminum heads, unported
 2.19" intake and 1.71" exhaust Manley Severe Duty valves
 1.73:1 ratio stainless roller rockers (Norris or Crower)
 Ford 4 bolt main cast iron 351C block
 SCAT 408C stroker kit (4-351C-4000-6000):
 4340 forged steel crank, 4.0" stroke, nitride hardened
 SCAT H-beam forged steel rods, 6" long, SBC journal
 Probe forged pistons, 16cc dish, 2618-T61 aluminum , full floating,
 1/16", 1/16", 3/16" rings, 1.2" CH, 435 grams w/o pin, p/n 14213-030
 Snout spacer (made by Dave McLain)
 Powerbond 9000 Series SFI balancer
 Pete Jackson quiet gear drive
 FRPP M-6500-S58 "Early Block Hydraulic Roller Lifter Set"
 10:1 compression
 408 cubic inches (4.03" bore by 4" stroke)
 Trend custom length push rods
 PMGR starter (Dennis Quella)
 Aviad Pantera gated and baffled road race oil pan
 Aluminum water pump (Dennis Quella modified with backing plate)
 Euro GTS Pantera headers with Mike Drew-modified ANSA mufflers

The above specs are how the engine will be installed in Mike's Pantera.  On
the
dyno, a Holley HP950 carb was used, along with long tube headers and
Magnaflow
mufflers.  The 950 in HP950 is misleading.  It's actually a 750 body
with an 850
baseplate and flows around 830 CFM.  No intake bellmouth was used on the
dyno
carb.  The headers used were Hooker Competition headers of 1 3/4"
diameter by 27"
long primaries with 3" diameter by 8" long collector (part number
HOK-6920HKR).
12 inch long collector extensions and 3" inlet/outlet Magnaflow
mufflers completed
the dyno exhaust.  We had an Innovate LM1 wide band O2 sensor plumbed into
the
header to keep an eye on the air-to-fuel ratio.

Mike had some set ground rules for the engine.  First he wanted to use the
Blue
Thunder intake manifold he had milled flat to fit under the stock
Pantera engine
screen.  Retaining the engine screen would also mean no spacer could be
used.
The 4V port size of the Blue Thunder intake dictated using either iron 4V or
aluminum CHI 4V heads.  Mike chose the CHI heads from Australia.  This
was to be
a best bang-for-the-bucks build so Mike wanted to use as many of the
parts as he
could from his previous poorly matched 351C.  For instance, the CHI 4V
heads were
purchased bare so we could re-use the Manley valves that were in his
open chamber
iron 4V heads.  Other parts Mike provided include steel roller rocker
arms, guide
plates, oil pump, gear drive, starter, gear drive, miscellaneous
fasteners, aluminum
flywheel and an aluminum water pump.  Mike also intends to use the
gutted Euro GTS
mufflers we previously tested.  This would figure into the cam selection.

The block is one I purchased from Steve Liebenow in 1997 when I carried two
complete 351C's in the back of my lowered 1987 Mustang GT from San Francisco
to
St. Louis.  The block has 4 bolt mains and was standard bore but had damage
in
one bore which required a sleeve and some rust pitting in other bores.
 The block
was sonic tested, bored 0.030" over and honed with a torque plate.
Mike chose a
SCAT 408C stroker kit to go with the CHI 4V aluminum heads and Blue
Thunder intake
manifold.   All engine assembly, along with the dyno services and
intake porting
were provided by Dave McLain of McLain's Automotive in Cuba, MO.  A
few pictures
of the short block and heads are at:

 http://s40.photobucket.com/albums/e218/DaveMcLain/Mike%20Drew%20408%20Cleve
land%20Engine/

Mike's based in California where 91 octane is the normal premium pump
gas and Mike
wanted to go conservative on the compression.  He also wanted to go
with a set and
forget hydraulic roller cam.  The cam was to be a street grind that
would work well
at track days, peaking around 6000 RPM and giving the best area under
the horsepower
curve, given the ZF 5 speed gear ratios.  I ran the numbers and
figured he'd drop
back to around 4000 RPM on shifts and designed the cam to give the
best area under
the HP curve between 4000 and 6000 RPM.  I could have gotten better
peak HP but at
the expense of area under the curve and low end response.  Given
Mike's exhaust and
carb choices, the cam chosen was a better all around compromise.

Dave flow benched the unported cylinder heads:

 Lift    Int    Exh
 0.025   14.1   10.5
 0.050   33.3   27.5
 0.100   65.7   60.2
 0.200  129.5  115.7
 0.300  186.2  150.8
 0.400  240.5  181.7
 0.500  287.5  199.0
 0.600  317.5  212.5
 0.700  329.6  221.7
 0.800  323.0  230.9

and I measured the intake, heads, headers, etc. to feed Dynomation the
required
information so I could design the cam using the Pro Iterator feature
in Dynomation.
The resulting figures were crossed against Bullet's CRA hydraulic roller
lobes.
The CRA lobes have a conventional nose (as opposed to a dwell nose
designed for a
lift-rule race class), a lobe shape good for RPM and/or high lift
rockers (applies
to the 351C's 1.73:1 rocker ratio and large heavy valves) and an
asymmetrical
opening/closing shape (helps with valve bounce).  I'll go into more
detail on using
Dynomation to design a cam when I post on the cam I designed for
Orville Burg (See
"A geek engineer designs a cam").  The resulting cam is a hydraulic roller
with
specs:

 236/240 degrees @ 0.050" (291/297 deg adv), 0.616"/0.596" lift, 108 LSA

using Bullet hydraulic roller lobes HR291/356 (intake) and HR297/344
(exhaust):

 Master Adv .050 .200 Lobe 1.73:1 Lash Type
 HR291/356 291 236 156 .3560 .6159 .000 CRA
 HR297/344 297 240 156 .3443 .5956 .000 CRA

The Bullet cam core is 1010 steel and requires a compatible distributor
gear.
The Crane/FRPP gears were in short supply but Mike found one at Precision
Proformance.  Supposedly, the gears are back in production and will be more
widely available soon.  Some 351C blocks can use the less expensive OEM Ford
hydraulic rollers with a standard base circle cam but many blocks cannot.
 It
depends upon the size of the chamfer at the top of the lifter bores.  The
Crane
p/n 36532-16 link bar retrofit roller lifters will work in all 351C blocks
and
can support higher RPM than OEM lifters.  The FRPP p/n FRPP M-6500-S58
"Early
Block Hydraulic Roller Lifter Set" are identical to the Crane lifters but
were
a bit less expensive when Mike purchased them.

The forged SCAT 351C cranks are made to Ford SVO specs and are essentially
351W cranks with 351C main bearing dimensions and SBC rod journals.  The
crank
will drop right into a 351C block but a snout spacer is required to
compensate
for the 351W dimension snout.  The FRPP part is obsolete so Dave McLain made
one for Mike's engine.  H-beam rods came with the SCAT stroker kit and fit
without any clearancing.

The engine had been previously run in for around an hour to seat the rings
and
several pulls made to determine the best overall timing.  An earlier 408C we
tested with iron 4V heads made it's best power at 32 degrees and the 351C
dyno
mule made best power at 38 degrees but, with the CHI aluminum heads, Mike's
408C made its best power on only 28 degrees total timing.

Out of the box, the Blue Thunder dual plane intake has 4 runners that flow
relatively well and 4 that flow relatively poorly. The Ford aluminum dual
plane
(Boss 351 copy with Holley carb pattern) also exhibits this
characteristic, though
the pattern of good and bad runners is different.  When we did Glen
Hartog's 408C
with iron 4V heads, the bare heads flowed 322 CFM at 0.6" lift.  When the
dual
plane Ford was bolted up, half the runners flowed in the 270's to 280's,
while
the other half were down in the 250's.  To equalize the flow in the
runners, the
center plenum divider was cut down and the port plenum entry radiused to
bring
the poor flowing ports up to match the good flowing ports.  On the Ford
intake,
a one inch spacer was also used.  However, on the Blue Thunder, no spacer
was
used to allow the most room for a decently sized drop base air
cleaner.  The carb
pad had been previously milled flat since the Pantera, unlike most front
engine
cars, mounts the engine level.  On the previous Blue Thunder (standard
version
with canted carb pad), after the plenum work, a typical "bad" runner went
from
250 CFM to 276 CFM so the improvement is substantial.

On Glen's 408C, the unported Blue Thunder was down 31 HP and 23 ft-lbs to
the
ported Ford dual plane.  A Strip Dominator (with 1" spacer) made 15 HP more
at
peak than the Ford so the unported Blue Thunder was down about 47 HP to the
Strip Dominator.  On Mike's 408C, the ported Blue Thunder and Strip
Dominator
were very close with the unported Blue Thunder intake lagging by maybe 15 HP
(see dyno results below).  There are several differences that may account
for
the better performance of the unported Blue Thunder this time around.

1. Mike's ported Blue Thunder has a flat pad which may harm the wet flow
characteristics of the manifold.

2. Mike's ported Blue Thunder has no spacer.  The previous Strip Dominator
and Ford intakes were tested with several 1" spacers.  We've seen 10+ HP
with the right spacer (varies from intake to intake).

3. Glen's 408C used iron 4V heads and Mike's used CHI 4V heads. The CHI port
entry shape is quite different than that of the iron heads and may be better
suited to the Blue Thunder intake runners.

4. Some intakes are more combination sensitive than others and I designed
Mike's cam to work best with the dimensions of the Blue Thunder intake.

Dave developed the intake on the flow bench without a spacer and subsequent
dyno testing showed the intake made the same power with or without a spacer.
In addition to the Blue Thunder dual plane, we had several other intakes
lined
up to test:

 Holley Strip Dominator single plane
 Offy 360 Equal Flow split plenum
 Edelbrock Scorpion single plane
 CHI 3V 4150 single plane
 Ford Motorsport A331 high port single plane
 Edelbrock Performer RPM Air Gap 2V dual plane
 Edelbrock F-351 4V dual plane
 Bud Moore Maxi Plenum
 Dual Autolite Inlines on Doug Nash IR manifold

Unfortunately, the CHI 3V and Ford Motorsport A331 intakes have raised
intake ports
and would not seal against the lower opening of the CHI 4V heads and
the Autolite
Inlines required debugging we didn't have time for.  In any case, Dynomation
predicted in the neighborhood of 520 HP at 6000 RPM for the Blue Thunder
intake
equipped engine, through the mufflers.  Initial pulls to set timing resulted
in
corrected numbers of 519 HP @ 5900 RPM and 498 ft-lbs @ 4900 RPM, also
through the
mufflers.  With both the single and dual planes, peak torque was 500
ft-lbs or more
with a wide flat torque band.  The lowest RPM pulled from was 3000 RPM and
the
engine was making in the range of 450 ft-lbs at that RPM.  Those
numbers were with
heat soaked intakes.  We also tested the Blue Thunder and Edelbrock
Scorion intakes
after they had cooled and they were in the 525+ HP range.

Dynomation predicted the Scorpion and Strip Dominator single planes
would be close
to the Blue Thunder but the Blue Thunder would have a slight edge in total
area
under the curve.  The Edelbrock Performer Air Gap 2V was predicted to
be not too
far behind, trading some HP for more torque.   The Offy was predicted to be
the
worst intake with the Edelbrock F-351 4V dual plane somewhere in the
middle, falling
off the pace after 4500 RPM or so.  The dyno results are listed below
and track the
predictions well.  As in previous dyno tests, Dynomation's prediction
is pretty close
on the peak HP but optimistic by 20 to 30 ft-lbs on the peak torque.
Note there are
a few missing tests below.  We had an intermittent ignition problem
that negated several
tests.  Eventually, the fault was traced to the timing controller so
Dave bypassed that
and set the timing manually.

I've got the data listed below plotted in an Excel spreadsheet and
will post a jpeg of
it later.  Comments are ones made when the engine was on the dyno.

Blue Thunder Jetting test
Still running with the HVH spacer but came down two jet sizes from 78
front 90 rear
(no power valve rear) to 76 front and 88 rear.  Seemed to help very
slightly near
the top end and engine made 522 at 5950rpm.

RPM     HP      Torque (ft-lb)
4000    374     492
4100    390     496
4200    398     498
4300    409     499
4400    420     501
4500    430     501
4600    441     503
4700    452     505
4800    457     500
4900    464     498
5000    473     496
5100    480     495
5200    489     494
5300    497     493
5400    501     488
5500    502     480
5600    504     473
5700    507     467
5800    513     464
5900    521     463
5950    522     461


Running with no spacer, 76 jet front 88 rear.  Took engine to 6200 RPM
and power is about
the same at peak with 519 at 5900 RPM.

RPM     HP      Torque (ft-lb)
4000    371     483
4100    378     485
4200    391     487
4300    402     491
4400    411     491
4500    419     489
4600    429     489
4700    441     492
4800    454     496
4900    464     497
5000    472     496
5100    479     494
5200    486     491
5300    493     488
5400    497     484
5500    500     477
5600    502     471
5700    505     465
5800    514     465
5900    519     462
6000    516     451
6100    508     438


Day 2 Testing

Test 1 Blue Thunder (ported)
Baseline pull for today good pull with a small misfire in the middle
of the pull, I think
a plug was loaded a little because we did some messing around warming
up the engine.  Same
as Test 9 from previous day, 28 timing, 76 and 88 jets in 950HP
straight (no spacer) on
the Blue Thunder intake.

RPM     HP      Torque (ft-lb)
4000    369     483
4100
4200    391     489
4300    403     492
4400    414     494
4500    425     496
4600    436     497
4700    447     499
4800    458     501
4900    464     497
5000    462     485
5100    464     478
5200    478     482
5300    488     483
5400    498     484
5500    505     481
5600    503     473
5700    504     465
5800    511     463
5900    519     462
6000    526     460
6100    507     437


Test 4 Holley Strip Dominator, no spacer
Baseline pull with the Stip Dominator intake manifold.  Seems as
though there is
not much difference between the two intakes right now but I need to go back
to
the 90 and 78 jet.

RPM     HP      Torque (ft-lb)
4000    369     482
4100    372     477
4200    385     480
4300    395     482
4400    403     481
4500    413     482
4600    423     483
4700    435     486
4800    449     490
4900    456     490
5000    465     488
5100    471     485
5200    476     481
5300    483     478
5400    490     477
5500    496     474
5600    492     461
5700    492     454
5800    496     450
5900    504     448
6000    508     444
6100    497     429

Test 5 Holley Strip Dominator
Back to the stock jetting in the 950HP and power picked up a little
with the Strip
Dominator.

4000    370     481
4100    376     479
4200    386     483
4300    395     483
4400    401     480
4500    410     479
4600    421     481
4700    434     485
4800    447     488
4900    457     490
5000    466     490
5100    484     495
5200    486     493
5300    490     486
5400    496     483
5500    500     477
5600    496     466
5700    495     456
5800    502     455
5900    513     457
6000    518     454


Test 7 Edelbrock Performer RPM Air Gap 2V
Fixed ignition glitch and found some torque and HP.  This intake is
down about 12 to 15
horsepower right at the top above about 5500 RPM but is superior down
lower.  Might be
the best all around compromise for the Cleveland but won't fit under
the Pantera engine
screen.

RPM     HP      Torque (ft-lb)
3900    383     512
4000    387     509
4100    396     508
4200    408     509
4300    416     509
4400    425     508
4500    435     507
4600    445     508
4700    451     505
4800    466     507
4900    466     500
5000    468     492
5100    474     488
5200    481     485
5300    484     480
5400    487     473
5500    489     467
5600    487     457
5700    490     451
5800    495     448
5900    501     446
6000    494     432


Test 8 Edelbrock Scorpion
Edelbrock Scorpion intake with 950HP.  Seems to be very good for
torque and HP when compared
to baseline or anything else.  Good solid torque and HP across the
board.  Will not fit on
Pantera but this intake does have a level carburetor pad.

RPM     HP      Torque (ft-lb)
4000    390     507
4100    393     505
4200    403     505
4300    414     505
4400    423     505
4500    433     505
4600    446     508
4700    457     511
4800    464     508
4900    473     507
5000    480     504
5100    486     501
5200    492     497
5300    499     495
5400    504     491
5500    507     484
5600    505     473
5700    507     467
5800    509     461
5900    516     460
6000    525     459


Test 9 Backup of Scorpion
Allowed intake to heat soak and did a pull from 3000 rpm.  After a
good heat soak, intake
produced more realistic power levels very much inline with our
baseline with the Blue Thunder
intake.  The Scorpion is essentially a Torker with an intergral spacer
and level carb pad.
The Scorpion works better on this engine than the Torker with spacer
did on Glen's 408C.

RPM     HP      Torque (ft-lb)
3000    253     440
3100    257     437
3200    265     435
3300    272     436
3400    291     445
3500    299     449
3600    308     451
3700    320     454
3800    334     462
3900    350     471
4000    366     480
4100    380     487
4200    393     491
4300    405     494
4400    416     497
4500    428     500
4600    442     503
4700    451     505
4800    459     503
4900    466     499
5000    474     498
5100    480     495
5200    487     492
5300    499     494
5400    503     490
5500    504     481
5600    503     472
5700    504     464
5800    507     459
5900    511     455
6000    510     446


Test 10 - Offy 360 EquaFlow
Started pull at 3000rpm as on the previous test.  Engine sounded ok
but power is off
somewhat with this intake as expected.  Down 30+ horsepower or so from
the baseline.

RPM     HP      Torque (ft-lb)
3000    244     427
3100    252     428
3200    261     428
3300    270     430
3400    279     432
3500    289     434
3600    299     436
3700    309     438
3800    319     440
3900    329     444
4000    342     449
4100    354     454
4200    366     458
4300    381     465
4400    394     471
4500    404     471
4600    413     473
4700    423     473
4800    432     473
4900    442     473
5000    445     468
5100    447     460
5200    448     453
5300    453     449
5400    458     445
5500    457     436
5600    455     426
5700    456     421
5800    461     416
5900    466     415
6000    467     408


Test 11 - Edelbrock Performer F-351 4V with 1" 4 hole spacer
Running from 3000rpm with the Performer intake and it works as
expected, good torque
at peak but torque falls quickly past about 4500rpm.  Wonder how well
it would work
given the plenum treatment the Blue Thunder received?

RPM     HP      Torque (ft-lb)
3000    264     461
3100    261     443
3200    272     447
3300    284     453
3400    298     460
3500    311     467
3600    324     473
3700    337     478
3800    349     482
3900    360     485
4000    372     488
4100    384     492
4200    395     494
4300    405     495
4400    414     494
4500    424     495
4600    434     496
4700    438     490
4800    444     488
4900    457     488
5000    460     485
5100    462     476
5200    466     471
5300    474     469
5400    477     464
5500    478     457
5600    474     444
5700    472     435
5800    475     430
5900    480     427
6000    479     419


Test 12
Bud Moore box intake with 4 hole 1 inch spacer.  Did not run
particularly well and
seemed to have rather weird changes in mixture with the wideband from
about 11:1 to
very lean and back again randomly through the pull.  Fuel puddling was
evident when
the top was removed.

RPM     HP      Torque (ft-lb)
3000    253     440
3100    258     438
3200    268     439
3300    278     442
3400    288     445
3500    299     449
3600    316     458
3700    328     466
3800    344     476
3900    358     482
4000    368     484
4100    380     487
4200    391     489
4300    402     491
4400    415     495
4500    426     497
4600    436     498
4700    444     496
4800    453     495
4900    459     492
5000    464     487
5100    469     483
5200    476     481
5300    481     477
5400    485     471
5500    486     464
5600    483     454
5700    480     442
5800    484     438
5900    486     432
6000    481     421


Test 13
Testing with a stock BT intake with no porting work.  Made good power,
about 497 HP at 6000rpm.  After a reasonable

amount of heat soak time.

RPM     HP      Torque (ft-lb)
3000    257     448
3100    263     446
3200    274     449
3300    284     452
3400    295     455
3500    307     461
3600    324     470
3700    335     475
3800    347     479
3900    357     482
4000    368     483
4100    379     485
4200    391     489
4300    404     492
4400    414     495
4500    424     496
4600    438     495
4700    440     492
4800    442     483
4900    449     481
5000    456     480
5100    464     477
5200    469     474
5300    477     472
5400    476     464
5500    477     454
5600    474     445
5700    473     436
5800    479     434
5900    488     434
6000    497     435
6100    469     405


Test 14 Back to Ported Blue Thunder
Went back to the modified BT intake with ported and milled plenum.
Made similar power but
we had changed jetting so power was down a little.

RPM     HP      Torque (ft-lb)
3000    247     434
3100    255     431
3200    263     432
3300    273     434
3400    283     437
3500    294     441
3600    306     447
3700    320     454
3800    334     462
3900    348     469
4000    360     472
4100    373     478
4200    385     482
4300    398     486
4400    409     488
4500    420     490
4600    429     491
4700    440     492
4800    451     493
4900    460     493
5000    464     488
5100    470     484
5200    477     481
5300    482     477
5400    487     473
5500    490     468
5600    490     459
5700    492     454
5800    496     449
5900    501     446
6000    509     445

Dyno Dan Jones
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